Hidden cameras and listening devices in my home installed by me.
Illegal or not ilegal? I have a 1 year old daughter and I think her
step sister is a little rough on her. My wife and I are divorcing and
I want to be assured that my daughter is protected. When ever I bring
up the question she calls the cops ar gets a resraining order on me. I
have no way of protecting my child.

Assuming you can't get explicit consent, illegal.
California Penal Code section 632(a):
632. (a) Every person who, intentionally and without the consent of
all parties to a confidential communication, by means of any
electronic amplifying or recording device, eavesdrops upon or records
the confidential communication, whether the communication is carried
on among the parties in the presence of one another or by means of a
telegraph, telephone, or other device, except a radio, shall be
punished by a fine not exceeding two thousand five hundred dollars
($2,500), or imprisonment in the county jail not exceeding one year,
or in the state prison, or by both that fine and imprisonment...
http://www.leginfo.ca.gov/cgi-bin/waisgate?WAISdocID=01939713320+4+0+0&WAISaction=retrieve
California's Supreme Court recently reiterated the meaning of a
"confidential" communication in a case involving the broadcast of the
aftermath of an automobile accident. The court stated that a
conversation is confidential for purposes of the eavesdropping statute
"if the circumstances objectively indicate that any participant
reasonably expects and desires that the conversation itself will not
be directly overheard by a nonparticipant or recorded by any person,
participant or nonparticipant."
http://www.rtnda.org/resources/hiddencamera/california.html
People v. Gibbons, 263 Cal. Rptr. 905 (Ct. App. 1989) established that
section 632 also applies to videotape, even if it does not record
audio.
Note that this applies only to recordings in places where there is a
reasonable expectation of privacy. Though it doesn't seem likely with
a young child, if any of this roughness happens in a public place,
there is no reasonable expectation of privacy, so such recordings are
legal. If it happens on a regular basis, you may be able to engineer
an outing and hire a private investigator to follow and record at a
distance.
Here's a link that provides some tips about recording surreptitiously
in places where there is not a reasonable expectation of privacy:
http://www.deltabravo.net/custody/taping.htm
While the baby is residing in your house, you may wish to consider
hiring a nanny to keep an eye on her while you are unable to. After
that, I'm afraid you're in more turbulent waters.
Search terms: california video recording "expectation of privacy"

whyme2-ga
rated this answer:
and gave an additional tip of:
$25.00

thank you for the research as well as the links for back up. i have
enough amunition to responsibly present my concerns.

This is really tough for you.
As a consequence of a divorce, the Court may give custody of your
daughter to the mother in any event.
But, if the mother can bring evidence that you have been doing
something illegal, this might harden the Court's decision against you.
You really need a good lawyer ... but, of course, these guys are VERY
expensive.

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